1. Field of the Invention
The present invention relates to a multilayer ceramic electronic component; and a multilayer ceramic electronic component showing favorable dielectric properties even when a dielectric layer is made thinner.
2. Description of the Related Art
A multilayer ceramic capacitor as one example of multilayer ceramic electronic components is widely used as a small-sized, high performance, highly-reliable electronic component, and there are a large number of multilayer ceramic capacitors used in electric and electronic equipments. Recently, with downsizing and increase in performance of equipments, demands for further downsizing, higher performance and higher reliability to the multilayer ceramic electronic component have been increased.
To respond the above demands, for example, a dielectric layer of the multilayer ceramic capacitor has been made thinner and increased in number of layers. However, for making the dielectric layer thinner, when a grain size of a dielectric particle is decreased specific permittivity is declined, so that desired properties may not be obtained.
Japanese Unexamined Patent Publication No H10-12476 discloses a multilayer ceramic capacitor wherein a continuity of an internal electrode is within the range of 70 to 95% when the thickness of a dielectric ceramic layer is made thinner to 20 μm or less. The continuity is defined as a ratio of a region where the internal electrode actually exists to a region to be formed an internal electrode. It discloses that according to the capacitor, it is possible to reduce variation in capacitance and to hardly cause an interfacial crack due to shrinkage distortion between the internal electrode and the ceramic layer at sintering even when the layers are made thinner.
However, there are problems such that the obtained capacitance may be declined because of the existence of a discontinuous portion in the internal electrode, and that high temperature accelerated lifetime may be lowered in the region where the thickness of the ceramic layer is several microns or less. Also, Japanese Unexamined Patent Publication No H10-12476 fails to disclose specific contents of components included in the dielectric ceramic layer.